Broadcast: News items

University of Sussex ecologist Mike Hutching's study of rare orchids has provided a powerful source of data for studying climate change, according to new research.

Professor Hutchings' collection from the Castle Hill National Nature Reserve was used in research published today (Wednesday 22 September 2010) in the British Ecological Society's Journal of Ecology.

The scarcity of reliable long-term data on phenology - the study of natural climate-driven events such as the timing of trees coming into leaf or plants flowering each spring - has hindered scientists' understanding of how species respond to climate change.

But ecologists from the University of Sussex, the University of Kent, the University of East Anglia (UEA) and the Royal Botanic Gardens, Kew have found that plants pressed by collectors up to 150 years ago tell the same story about warmer springs resulting in earlier flowering as field-based observations of flowering made much more recently.

The team examined 77 specimens of the early spider orchid (Ophrys sphegodes) collected between 1848 and 1958 and held at the Royal Botanic Gardens, Kew and the Natural History Museum in London. Because each specimen contains details of when and where it was picked, the researchers were able to match this with Meteorological Office records to examine how mean spring temperatures affected the orchids' flowering.

They then compared these data with Professor Hutchings' field observations of peak flowering of the same orchid species in the Castle Hill National Nature Reserve, East Sussex, from 1975 to 2006, and found that the response of flowering time to temperature was identical both in herbarium specimens and field data.

In both the pressed plants and the field the results are first direct proof that pressed plants in herbarium collections can be used to study relationships between phenology and climate change when field-based data are not available, as is almost always the case.

Professor Hutchings says: "Scientists have long suspected that these dusty archives might help us understand the effect of climate change on plants and this is the first study to prove that hypothesis. The great thing about this is that we can now predict flowering times more reliably and subsequently predict the activity of pollinators. Ultimately this discovery will help us to know whether we will be able to grow food in the same way in the future."

The study opens up important new uses for the 2.5 billion plant and animal specimens held in natural history collections in museums and herbaria. Some specimens date back to the time of Linnaeus (who devised our system of naming plants and animals) 250 years ago.

It is hoped that similar principles could be extended to museum collections of insects and animals.

Notes for editors

Karen M Robbirt et al (2010), 'Validation of biological collections as a source of phenological data for use in climate change studies: a case study with the orchid Ophrys sphegodes', doi: 10.1111/j.1365-2745.2010.01727.x, is published in the Journal of Ecology on 22 September 2010.

The early spider orchid (Ophrys sphegodes) is a species of southern and central Europe, with a northern range that includes southern England. It is associated with ancient, species-rich grassland over calcareous soils. Rare in the UK, the species is largely confined to Dorset, West and East Sussex and Kent.

The Herbarium at the Royal Botanic Gardens, Kew contains some eight million preserved plant and fungal specimens, representing 98 per cent of all known genera. Each year the collection grows with over 35,000 new additions. In autumn 2010, a new extension is being launched as part of the Royal Botanic Gardens, Kew's celebrations to mark the United Nation's International Year of Biodiversity. For more information, visit www.kew.org/ucm/groups/public/documents/document/ppcont_016015.pdf

The British Ecological Society is a learned society, a registered charity and a company limited by guarantee. Established in 1913 by academics to promote and foster the study of ecology in its widest sense, the Society has 4,000 members in the UK and abroad. Further information is available at www.britishecologicalsociety.org